To try and extrapolate some form of conclusion out of those stats is equally silly. They mean nothing.
Using the stats on their own perhaps not i would be inclined to agree, but all these stats are providing is statistical evidence to confirm what the majority of United fans already think from watching United's performances this season when Fellaini starts in CM. Which he has done for the majority of his games this season.
Whenever he starts in there we are a worse side, we can all see it even if we don't all want to admit it yet. He offers little if anything in attack, slows down play and abandons his midfield partner and leaves our midfield wide open to be overran.
In that context when you then look at these stats, well they paint a picture.
Without Felllaini:---------------------With Fellaini:
P - 30--------------------------------P - 18
W - 17 = 56.6%---------------------W - 06 = 33.3%
D - 07 = 23.3%---------------------D - 06 = 33.3%
L - 06 = 20.0%----------------------L - 06 = 33.3%
For whats its worth last season whenever he played in the side further up the pitch in his more natural position (which he did for the most part) i thought we were a better side with him than without and i'd bet the same sort of stats would back that up.
Edit: Heres the same stats from last season.
With Fellaini:-------------------------Without Fellaini:
P - 23--------------------------------P - 21
W - 14 = 60%-----------------------W - 09 = 42%
D - 03 = 13%------------------------D - 08 = 38%
L - 06 = 26%------------------------L - 04 = 19%